#!/bin/bash

# block read testing
# give it a device and it will go after it


if [ -z "$3" ] ; then
    echo "Usage: $0 device count percent"
    echo "	device : device to test(eg. /dev/sda)"
    echo "	count : number of blocks to test for each chunk"
    echo "	percent : percentage of disk surface coverage"
    exit 2
fi

renice +5 -p $$
bsize=1024
count=$2
percent=$3

disksize=`fdisk -l $1 | grep -m 1 $1 | awk '{print $5}'`
let disksize="$[disksize/bsize]"
echo "disksize : $disksize"
let chunks=$[disksize/count]
echo "chunks : $chunks"
let blocks=$(echo "($chunks * $percent / 100)" | bc)
echo "blocks : $blocks"
let interleave=$(echo "($chunks / $blocks)" | bc)
echo "interleave : $interleave"

echo "
Sequential Disk Test
Disk coverage = $percent%, $((count*blocks*bsize/1024))KB 
Chunk Size = $((chunks/1024))KB
blocks = $blocks
interleave = $interleave"

for ((i=0; i <= blocks ; i+=1))
do
  let "start=count*i*interleave"
  let "end=start+count"
  echo "Testing at location $((100*end/disksize))% - $start to $end - $i of $blocks  "
  badblocks -b $bsize $1 $end $start 2&>1
done
exit $?
